Printing ink



g- 7, 1945- c. E. IRION 2,381,753

PRINTING INK Filed Jan. 3, 1941 (INFLAMMABLE) H YDRDGEN 1C2H6 CzFflS 'T'C CL 12 11 1o 9 a 2 FLUORINE L CHLORINE non-mxuqansaOus) (TOXIC) grime/WM eda-Lu Mao-Q Patented Aug. 7, 1945 PRINTING INK Clarence a. men,

General Montclair, N. 1., asslgnor to Printing In]: Corporation, New York,

N. Y., a corporation of Delaware ApplicatlonJanuary 3, 1941, Serial No. 378,048

18 Claims.

This invention relates to rotogravure inks, and more particularly to rotogravureinks which are both non-toxic and non-inflammable.

The rotogravure printing process as usually carried out involves printing from an intaglio roll with relatively fluid inks which dry by the evaporation of very volatile solvents. Such solvents have been selected in the past so as to dissolve the binder-used, and to provide evaporation at the desired very rapid rate. Unfortunately, all such solvents have been either highly toxic or inflammable, and the majority have possessed both of these undesirable characteristics. This is particularly true of the aromatic hydrocarbons such as benzol and toluol which heretofore have been considered the rotogravure solvents of greatest utility.

The very nature of the printing press operation makes control of the resulting iire and health hazards extremely difficult if not impossible. No simple ventilation system has been devised which will remove the vapors from, the region .of the presses to such an extent as to eliminate localized high concentration of the solvents in positions in which the workmen will be exposed to their toxicity. The character of the presses used makes a satisfactory solvent recovery system such as used in some other industries diflicult and expensive because of diiiiculties of applying such a system to a machine handling a printed web or sheet which will not contact or smudge the freshly rinted subject... The rapid operation of the machines causes continuous generation of static electricity, and although this is systematically eliminated ordinarily by grounded conductors, sparks are by no means infrequent and if such a spark occurs in thepresence of an explosive or inflammable solvent mixture, av dangerous fire is likely to result, the seriousness ofwhich is further'increased by the presence of large quantities of paper upon the presses and at other points in the pressrooms.

Ever since the development of rotogravure printing a constant but unsuccessful search has been carried on to flnd or devise practicably usable solvents or solve t combination suitably free of the hazards of tzxicity and inflammability. As a result solvents have been found which were free of one or the other of the two hazards, but in no case were both hazards eliminated in any usable solvent or solventcombination.

Recently, the extreme toxicity of the usual aromatic hydrocarbon materials has caused the substitution, in certain cases, of other materials found to be functionally sumcient and also less toxic-for example, the petroleum hydrocarbons in admixture'with certain other organic solvents. These substitution solvents decreased the health hazard, but failed to eliminate the fire hazard, as the petroleum hydrocarbons found usable are even more inflammable than the aromatic solvents of the same volatility. Of course, non-inflammable solvents are known-e. g., the chlorinated hydrocarbons, such as carbon tetrachloride; but such solvents are too toxic for printing inks, being as injurious or even more so than the aromatic hydrocarbons.

It is an object of the present invention to provide adequately and commercially available rotogravure printing inks which are non-toxic. and non-inflammable inuse. v

It is another object to provide a solvent for the binder of an ink which is sufficiently volatile for rotogravure inks, and the'like, and which still gives fumes on evaporation which are free from the objectionable health hazards of undue toxicity and inflammability.

It is still another object to provide certain fluorochloroalkanes having a predetermined compositionselected to give an intermolecular relationship which gives an evaporation range within the temperature limits of substantially 40 to 200 (3,: adequate solvent powers for the resins, bitumens, cellulose acetates, etc., ordinarily used I as the binder of rotogravure inks, or the like; and which also are substantially free from objectionable toxicity and infl'ammability, in use.

It is a further object of theinvention to provide such a non-toxic and non-inflammable solvent consisting of a fluorochloroalkane in'which the substitution of the fluorine and chlorine is controlled to give a predetermined limited relationship of fluorine to chlorine, and the fluorine and chlorine jointly are controlled with reference to the retained hydrogen to give a predetermined relationship in which the summation of the fluorine plus chlorine is at least one-half the retained hydrogen.

Further objects'and advantages of the invention will appear as hereinafter set forth. a

In the practical use of my invention fluorochloroalkanes are utilized as a part or all of the solvent component of my rotogravure ink. It has long been known that the chlorinated hydrocarbons are all highly toxic; and more recently it has been discovered in connection with certain chlorinated compounds, that if part of the chlorine of such chlorinated hydrocarbons is replaced by fluorine-another highly toxic materialthe resulting compound retains its non-inflammability characteristics and also is relieved of its toxicity. I have now discovered that certain fluorochloro substituted hydrocarbons of predetermined intermolecular relationship can be used to prepare rotogravure inks which are completely noninflammable in use, and which are likewise com- .fluorochloroalkanes have of ethane. That of 2 carbon atoms with hydrogen, chlorine and. 1 'fluorine, each varying from to 'fi-atoms' inclusive, in the ethane structure, are illustrated.

For purposes of simplicity "this 'chart shows the. 'fluorochloroalkanes empirically, .as' it hasbeen all the certain compounds used.

-] In this chart, a lateral triangle marked .Hydrogenfl represents variables with C2, "which are indicated on thechart-by the numbers from'l to 28 placed pletely innocuous as 't toxicity. These certain been'discovered to be adequate solvents to put in solution a suflicient amount of gum, resin, etc., to give such viscosity, metal adhesion,

Thesefluorochloroallranes are suitable solvents for the gums,.-resins, and bitumens, and also for the cellulose derivatives 'a binder of. solvent release, etc., as to serve as a practicably suflicient solvent for rotogravure inks and inks of the. desired non-toxic and non-inflammable characteristics.

the like and to provide" and the like, used in-the manufacture of roto-. gravure inks, and can be used either alone or when properly admixedwith other solvents.

Also, I have now found chloroalkanes have suitable solvent characteris tics and also. when in solution, tility as to give evaporat on and solvent release equal to high grade rotogravure inks now made and used commercially. In selecting that certain fluoro-QI have such .vola-.,

such as those rotogr'avure solvent combinations made upof fluorochloroalkanes of the proper relationship to give the desired non-toxic and nori-inflammability characteristics, I have found that nevertheless a wide range of boiling available, so'that suitableinks of any desired speed" or evaporation rate may be secured. Andfor inks comparable in evaporation speeds to those industry, fluo'rochloroalk'anes' presently used in of similar or somewhat higher boiling points can be used. The fluorochloroalkanes used in general have volatilities somewhat higher than-hydrocar-v bons of corresponding boiling points. so that a higher boiling fluorochloroalkane can be. used to obtain an'ink of the same speed of evaporation.

According to present chemical knowledge available to me, all the theoretically possible fluorochloroalkanes derivable from a given hydrocarbon can be mathematically determined. The accompanying chart, which, is set forth forillustrative purposes in describing my invention, shows all the possible fluorochloro substitutions is, all the various combinations found that with in practical operations, underthis-invention and as specified herein, thecharacteristics of the several isomers are so nearly the same that. any-of the several isomers will'give substantially the same desirable results in practical printingoperationathe' top intersection offthe equicomplete saturation with hydrogen, that is, represents the compound ethane (Cal-I6). The right v hand corner represents completesaturation withchlorine, thatis the compound hexachloroetha'ne (CzCla). The left hand; corner represents compoints and volatilities arev The more highly fiuorinated the compound the less tonic it becomes, as apparently the toxicity creases.

,molecule, the boiling point decreases as the chlorine to fluorine ratio de- The higher the ratio of fluorine to chlorine the lower the toxicity. In actual operations it has been found that at least two fluorine atoms should be present to insure completely adequate non-toxicity. Moreover, as chlorine atoms are successively-substituted by fluorine atoms in the drops. The fluorine atom appears to influence the boiling point to about the same degree as would an hydrogen atom inthe same position. From this discovery it is possibleto predict, at least in an approximate manner, about what the boiling point of any fluorochloroalkane will be, knowing the boiling points of the corresponding hydrocarbon and that of the corresponding completely chlorinated material, and as it has been discovered that-the volatility of these certain specified fiuorochloro- 'alkanes is higher than that of the hydrocarbon of corresponding boiling point, suitable allowance can be made in selection to give comparable press conditions.

I have found that many of the fluorochloro- -.a-lkanes are of such character that they can be used as a rotogravure solvent to give suitable printing characteristics but that compounds with relatively few hydrogen atoms are to be desired for the reasonthat they are less inflammable and for very desirable commercial results a ratio of at least one halogen to two hydxogens, so far,

has been found desirable.

In general the derivatives of. ethane, propane and butane, i. e., those a compounds. having2 to 4 carbon atoms inclusive, appear to be most suitable, not only in yielding plete saturationwith fluorine, i. e., hex'afluoro ethane (CzFo) The-remainingintersections show all the intermediate combinations of the. three Thus all these compounds at the intersections are as follows:

1. Cal-[0,. ethane 1 2. CzClHs, monochloro ethane" 3. CzClaI-h, dichloro ethane 4. C'zClzI-l's, trichloro ethane 1 v 5. CzChHz, tetrachloro ethane 6. C2ClsI-I, pentachloro ethane compounds of suitable boiling points and evaporation characteristics, but also because the noninfiammability characteristic of the compounds in the selected range tends to be less as the'number of carbon atomsiand accompanying hydrogen atoms increases, unless-the hydrogen atoms are almost completely substituted by halogens, in which case the boiling points are in general too high for practical use under present printing conditions.

Thus some fluorochloroalkanes other than those so far found commercially usable may be suitable in rotogravure inks of special characteristics.

. Those most useful under present printing conditions, in which solvents are used having boiling points varying from 40 C. to 200 C., are the than atoms.

specifled ethane and propane derivatives. Illustrative of such solvents are those of the ethane series lying in a restricted portion oi the illustrated chart, embracing the area having 2 or more fluorine atoms and less than 4 hydrogen atoms and indicated by the enclosing dotted line.

- Ihls gives the desired non-toxicity and non-inflammabillty, and the number of fluorine atoms is selected so as to yield a compound of the desired boiling point. Thus 01 the substituted ethanes, the diiiuoro dichloro (23), difluoro trichloro (27), and difluoro tetrachloro (9) ethanes are all suitable; as is also the trifluoro trichloro (i0) ethane.

The trifluoro dichloro ethane (26), which has a boiling point of approximately 28 0., would be suitable for a very fast ink, i. e., a very rapidly evaporating ink; and difluoro monochloro ethane which has a boiling point of approximately 35 0., would also be useful i'or an ink somewhat faster than those more generally used. These, like the remaining more highly fluorinated compounds, might be used ii suitable cooling or reirigeration should be resorted'to during printing Diiluoro monochloro pro- Trifiuoro trichloro propane Trifluoro tetrachloro propane Trifluoro pentachlo'ro propane Tetrafluoro dichloro propane Tetrafluoro trichloro propane Tetrailuoro tetrachloro pro- Pentafluoro trichloro pro- Pe gi uoro dichloro propane pane which have such volatility, and the other'desirable characteristics described, that they will make practical, satisfactory inks when admixed, alone or blended, as described. The volatility of the trifluoro monochloro, the tetrafluoro monochloro, the pentafluoro monochloro, the hexafluoro monochloro, the hexafluoro dichloro, and the heptafluoro monochloro propanes prevents their use under present printing operations; but if suitable refrigeration or other preventative of too ready evaporation should be provided these too might be used, as well as the derivatives containing only fluorine and hydrogen, 1. e., nochlorine provided the hydrogen is not present to the extent of more Such illustrative charts for propane and butane are thought unnecessary for purposes of description and understanding of the invention, suitable non-inflammable and nontoxic compounds of suitably selected boiling points being readilydetermined from the above data which may be easily applied in use by the formula- CIIHIIFICIy; wherein n is 2 to 4 inclusive; :1: is 2 to 10 inclusive; y is 0 to 8 inclusive; and p is determined by pane Difluoro dichloro propane Difiuoro trichloro propane Difluoro tetrachloro propane Difluoro pentachloro propane Difluoro hexachloro propane Trifluoro dichloro propane .not burn.

to be not less than one-half, and in which the sum 01' p, 1:, and u is always equal to 2-+2.

Certain similar selections of usable compounds can be made irom the higher homologs, having regard for the non-toxic, non-inflammable and boiling point characteristics as indicated.

The inflannnability characteristics of some of the common rotogravure solvents are listed below in the table.

TAIL! Flash pomte of rotaaraimre solvents and solvent mixtures solvent Flashlyoint,

Bcnzol 1 Toluol... 40 V.M.&P.naphtha 20-45 Methyl ethyl kctoic 3 Ethyl alcohol 55 Ethyl acetate 24 Isoprop ,vl alcohol 53 Petrolcne -4 Difluom dichloro ethane None Difluorn tctrachloro ethane None Difluoro trichloro ethane None Monofluoro trichloro ethane. None Difluoro pentachlnro propane None Percent by weight Textile spirits 75 Methyl ethyl kctone 25 Diiiuoro trichloro ethane 30. 9 Difluoro tetrschloro ethane 12.7 N Trifluoro tetrachloro propane 35. 1 one V. M. & P. naphtha 2L3 Difluoro trichloro ethane. 40. 0 Difluoro tetrachloro ethane. 12.9 N 'Irifluoro totrschloro propane 23. B one V. M. 6: P. naphtha 23. 3

This mixture is a widely use! commercial rotogravure solvent mixture.

It will be observed from the table that the fluorochloroalkanes have no flash point and will 4 "Petrolene,. on the other hand, which is an aliphatic hydrocarbon mixture having a boiling range of about 142 F. to 202 F., and commonly used in rotogravure inks, has the extremely low flash point of 4 F., that is, it will flash at a temperature even below freezing. Other materials show somewhat higher flash points but are decidedly dangerous from the standpoint of fire hazard in being below the limit of 27 C. specified by the Interstate Commerce Commission as requiring a red label for shipment in interstate commerce. The inflammability data is given in the form of flash points determined according to the A. S. T. M. method D 58-36 by means of the Tagliabue closed cup apparatus.

A single fluorochloroalkane can be used as-the entire solvent component of my inks, as illustrated below by Example I, or several may be blended together as in Example II, to produce the desired evaporation range curve as is customary in solvent blending. In this connection it is desirable to so blend the solvent constituents of the inks as printed, that the combined evaporation characteristics will be such that a preponderance of the solvent evaporates relatively quickly to insure rapid drying, but that an adequate amount of active solvent is present at all stages of the evaporation, and particularly toward the end, to maintain the resinous and bituminous constituents in solution and the ink sufliciently fluid to insure adequate flow and a resulting good lay of the trated in the table and in Examples III, IV and V, and when so blended in proper proportions will impart their characteristics or non-inflammability and. non-toxicity to the degree in which they are used.

Example II illustrates the use 01' several fluorochloroalkanes blended with respect to boiling points and exaporation rates to give the desired smooth evaporation curve, and Examples III, IV and V illustrate a compound blend 01' fluoroalkanes and another solvent to have such characteristic. The proportions required to give the desired increase in flash point of the non-fluorochloroalkane may be readily determined. For example, the V. M. 8: P. naphtha of Examples I11 and IV, which is essentially a diluent, has a boiling range of approximately 100-160 C., while the approximate boiling points oi! the fluorochloalkane's used are-difiuoro trichloro ethane 12 C., difluoro tetrachloro ethane 92 C., trifluoro tetrachloro propane 130 C. Thus the fluorochloroalkane content of the ink is adequate at all times during the evaporation to maintain the resinous or bituminous material in solution, while the naphtha insures adequate fluidity or the material throughout its range of evaporation.

I have discovered that many solvent combinations which flash below the danger point, can be raised to comparativesafety by the use oi. relatively small proportions of the fluorochloroalkanes. When the fluorochloroalkanes are used alone or in proper admixture with each other, or in proper relative admixture with other materials, as rotogravure ink solvents they impart their high degree of non-inflammability and non-toxicity to the ink. The fluorochloroalkanes are non-toxic even in high concentrations. No danger to life is observed except as concentrations may be so high as to leave serious doubt as to whether the effect is due to oxygen deficiency resultin from the displacement of air by the fiuorochloro compound rather than to the fiuorochloro compound itself. From the practical viewpoint of health hazards these compounds, as used in inks under the present invention, are entirely non-toxic.

Formulas for rotogravure inks suitable from the point of view of non-inflammability and nontoxicity and having very satisfactory operating characteristics, are given below.

EXAMPLE I.BLAcK INK Trifluoro tetrachloro propane 26.00 Gilsonite 15.54 Para red pigment .86 Clay 2.60

EXAMPLE III.Baown rm v, I Percent by weight Difiuoro-trichloro ethar ie 32.50 Difluoro tetrachloro ethane 10.55 Trii'luoro tetrachloro propane 19.35 V. M. a P. na1:ihtha 19.10 Gilsonite 15.00 Para red pigment .86. Clay 2.64

Exxmru: IV.BLur.' INK Q Percent by weight Difluoro trichloro ethane 25.00 Difluoro tetrachloro ethane 10.30 Trifluoro tetrachloro propane 28.38 V- M. 8: P. naphtha 17.22 Batu res 12.10 Synthetic resin (alkyd) 1.90 Milori blue pigment 3.20 Aluminum hydrate 1.90

EXAMPLE V.Rnn INK Percent by weight Difiuoro dichloro ethane 45.00 Difluoro tetrachloro ethane 10.00 Cellulose triacetate 10.00 Para re 8.00 Arochlor resin (chlorinated diphenyl) 4.00 Plasticizer 6.00 Leveling agen (.00 Inert filler 10.00

As pointed out above, these fluorochloroalkanes are excellent solvents, not only for the asphalts and gilsonites which are so widely used as binders in brown rotogravure inks, but also for a great many of the commonly available natural and synthetic resins, including rosin, damar, ester gums, alkyd, phenol-aldehyde, chlorinated diphenyls (Arochlors) and many others. The copals, shellac and vinyl resins, as well as some of the hard waxes such as carnauba wax are not soluble in the fluorochloroalkanes. Furthermore, the fluorochloroalkanes are excellent solvents for cellulose derivatives; and it has been discovered that they are excellent solvents for unhydrolyzed cellulose triacetate. This is a very non-inflammable cellulose derivative, which is practically insoluble in most of the common organic solvents. The usual commercial cellulose acetates are prepared by forming cellulose triacetate. and then hydrolyzing this initially formed cellulose triacetate so as to improve, and give it commercially usable, solubility characteristics. I have discovered that these fluorochloroalkanes will act as excellent solvents for this initially formed cellulose triacetate, and as a result this relatively inexpensive grade of cellulose triacetate, can be used and put into solution without the expense and diiiiculties in manufacture which are incident to the treatments heretofore given to change it from its initial formation, and the resulting solution, as a composition of matter, can be used in varying proportions as binders,- coatings, etc., in fields and for purposes other than the preparation of inks or binders and solvents therefore.

While the composition herein described constitutes a. preferred embodiment oi the invention, it

printing.

solvent release.

I assures is to be understood that the invention is not limited thereto and that changes may be made therein without departing from the scope or invention which is defined in the appended claims.

.What is claimed is: 1. A non-toxic, non-inflammable rotogravure ink comprising a pigment, and a binder material dissolved in a solvent comprising as an essential major component a fluorochloroalkane having a boiling point within the range substantially 40 to 200 0., the solvent being present in major proportion forming an ink having solvent release and high speed of evaporation providing adequate flow and lay of the ink on the paper.

2. A non-toxic, non-inflammable rotogravure ink comprising a pigment, and a binder material selected from the group consisting of natural resins, synthetic resins, asphalt, gilsonite, and cellulose acetate, dissolved in a solvent comprising a fluorochloroalkane containing more than one and less than five carbon atoms, the solvent being present in the ink in major proportions formingv an ink having high speed of evaporation and solvent release suitable for rotogravure 3. A non-toxic, non-inflammable in a fluorochloroalkane solvent having at least I one chlorine atom, at least two fluorine atoms I a ratio of halogen tohydrogen of at least-1 'tb i, the solvent being present in the ink in major {proportion providing an ink having a boiling Point-within the range of substantially 40 to 200C. and high speed 01 evaporation and good '4. A non-toxic, non-inflammable rotogravure ink comprising a pigment, and a binder dissolved in a solvent having the formula 6.1515611; where nis-2to4inclusive; zis2to loinclusive; yiso to B inclusive; and p is determined by ,to be not less than one-half, and in which the I" sum 01' p. 1:. and v is always equal to 2I+2I the a solvent being present in major proportion forming an ink having boiling point, volatility, high Speed: of evaporation and solvent release characteristics adequate for rotogravure printing. 5. A rotogravure ink as defined in claim 1 in which the fluorochloroalkane solvent has two carbon atoms, not less than two fluorine atoms, and less than tour hydrogen atoms.

6. A rotogravure ink as defined in claim 1 in which the fluorochloralkane solvent has three carbon atoms, not less-than two fluorine atoms,

and less than five hydrogen atoms.

7 Arotogravure ink as defined in claim 1 in which the fiuorochloralkane solvent has tour carbon atoms, not less than two fluorine atoms, and

. I less than six hydrogen atoms.

8 A non-toxic, non-inflammable rotogravure 'ink\,comprising apigment and a binder material dissolved in a solvent comprising a fluorochloro- -alkane selected from the 'groupconsisting of di fluorodichloroethane, difluorotrichloroethane, di-

fluorotetrachloroethane, and trifluorotrichloroethane, and having a boiling point within the range of substantially 40 to 200 0., the solvent being present in the ink in major proportion forming an ink having volatility, solvent release, and speed of evaporation characteristics suitable for rotogravure printing.

9. A non-toxic and non-inflammable solvent rotogravure ink comprising a pigment, and a binder dissolved mixture adapted for dissolving a pigment and a binder to form rotogravure inks comprising a mixture of fluorochloroalkanes selected to give a blend having a substantial evaporation range such that a preponderant portion of the solvent evaporates more quickly than the minor portion whereby rapid dryi is secured, but delay in the evaporation of the minor fraction insures adequate flow and lay of the ink upon the paper as 10 with other known inks of equivalent characteristics as to printing, said solvent mixture comprising a mixture of fluorochloroalkanes each having from two to four carbon atoms, not less than two fluorine atoms, and a ratio of halogen to hydrogen 01 at least 1 to 2.

- 10. A non-toxic solvent mixture adapted tor dissolving a Pigment and a binder to form rotogravure inks comprising a major fraction including a fluorochloroalkane having from two to four carbon atoms, not less than two fluorine atoms, and a ratio of halogen to hydrogen of at least 1 to 2, and a minor proportion of other aliphatic -solvent material having a boiling range of approximately IOU-160 C. blended with said major 5 fraction to give a smooth evaporation curve i'or proper flow and lay of the ink upon the paper, the fluorochloroalkane fraction having a boiling range lower than that oi said other aliphatic solvent material, and said composite solvent hav 3ov a flash point of not less than 27 0., determined whereby rapid drying is secured, but delay in 4|) evaporation of the minor fraction insures adequate flow and'lay of the ink on the paper, as with other known inks of equivalent characteristics as to printing, said solvent comprising a mixture of fluorochloroalkanes each having from two to tour carbonatoms, not less than two fluorine atoms, and a ratio of halogen to hydrogen 0! at leastl to 2'.

12. A non-toxic, non-inflammable rotogravure ink comprising a pigment and a binder dissolved in a solvent comprising a'mixture o1 fluorochloroalkanes selected to give a blend having a substantial evaporation range such that a preponderant portion of the solvent evaporates more quickly than a minor portion whereby rapid drying is secured, but delay in the evaporation in the minor fraction insures adequate flow and lay of the ink on the paper, as with other known inks of equivalent characteristics as to printing, said solvent comprising a mixture of fluorochloroalkanes each having from two to four carbon atoms, not less than two fluorine atoms, and a ratio of halogen to hydrogen 0! at least 1 to 2, said binder being selected from the group consisting of natural resins, synthetic resins, asphalt, gilsonite and cellulose acetate. 1

13. A non-toxic, non-inflammable rotogravure ink comprising a pigment and a binder dissolved in a solvent comprising a major fraction includ- 70 ing at least one fluorochloroa'lkane having from two to four carbon atoms, not less than two fluorine atoms, and a ratio o1 halogen to hydrogen of at least 1' to 2, and a minor fraction of other aliphatic solvent material which is more inflammable than afluorochloroalkane, said other solvent material having a boiling range of approxi mately 100-160 C., the nuorochloroalkane fraction having a boiling range lower than that of the other said aliphatic solvent and eflectivewith respect to the normal flash point of said other solvent to provide a composite having a. flash point 01' not less than 27 0., determined as described;

'alkane.

15. As a composition of matter, unhydrolized cellulose triacetate as formed as a separated reaction product dissolved in a non-toxic, noninflammable solvent comprising a fluorochloroalkane having from two to four carbon atoms, not less than two fluorine atoms, and a ratio oi halogen to hydrogen of at least 1 to 2.

16. A non-toxic, non-inflammable rotogravure ink comprising a binder dissolved in a solvent CERTIFICATE OF cosnscrrou.

Patent No. 2,581,755

It is hereby certified that error appears in: the printed specification ing a boiling pointwithin the range of substan CLARENCE 1;; 11111011.

' comprising at least one fluorochlor'alkane having iromtwo'to four carbon atoms, not less than two fluorine atoms, and-a ratio or halogen to hydrogen oi at least 1 to 2; said binder comprising unhydrolized cellulose trlacetate soluble directly in said solvent, and a coloring agent suchas a pigment.

' 1'1. A non-toxic,.non-inflainmable rotogravure ink comprising a binder material consisting of unhydrolized cellulose triacetate dissolved directly in a solvent comprising a fluorochloroalkan'e havtially 40 to 200 C. v

18. A non-toxic rotogravure ink comprising a binder material, a coloringmaterial and a fluorochloroalkane solvent component, said fluorochioroalka'ne having=aflash point above 27 0. and a boiling. point within the range ofsubstantially-iO to 200 C.

E. IRIoN,

of the above numbered patent requiring correction fas follows :Page 3 sec- 0nd column, -for the numeral "'1" line 18, in the Table, second column thereof, opposite "Benzol" read --l2'.-f-; and that thesaid Letters Patent should be read with this correction therein that the saine my; conform to the record of the case in the Patent Oiffi'ce.

Signed and sealed this 20thday of (Seal) November, I915.

Leslie Frezer"* First Assistant cmlsmnsr of Patents.

vent material having a boiling range of approxi mately 100-160 C., the nuorochloroalkane fraction having a boiling range lower than that of the other said aliphatic solvent and eflectivewith respect to the normal flash point of said other solvent to provide a composite having a. flash point 01' not less than 27 0., determined as described;

'alkane.

15. As a composition of matter, unhydrolized cellulose triacetate as formed as a separated reaction product dissolved in a non-toxic, noninflammable solvent comprising a fluorochloroalkane having from two to four carbon atoms, not less than two fluorine atoms, and a ratio oi halogen to hydrogen of at least 1 to 2.

16. A non-toxic, non-inflammable rotogravure ink comprising a binder dissolved in a solvent CERTIFICATE OF cosnscrrou.

Patent No. 2,581,755

It is hereby certified that error appears in: the printed specification ing a boiling pointwithin the range of substan CLARENCE 1;; 11111011.

' comprising at least one fluorochlor'alkane having iromtwo'to four carbon atoms, not less than two fluorine atoms, and-a ratio or halogen to hydrogen oi at least 1 to 2; said binder comprising unhydrolized cellulose trlacetate soluble directly in said solvent, and a coloring agent suchas a pigment.

' 1'1. A non-toxic,.non-inflainmable rotogravure ink comprising a binder material consisting of unhydrolized cellulose triacetate dissolved directly in a solvent comprising a fluorochloroalkan'e havtially 40 to 200 C. v

18. A non-toxic rotogravure ink comprising a binder material, a coloringmaterial and a fluorochloroalkane solvent component, said fluorochioroalka'ne having=aflash point above 27 0. and a boiling. point within the range ofsubstantially-iO to 200 C.

E. IRIoN,

of the above numbered patent requiring correction fas follows :Page 3 sec- 0nd column, -for the numeral "'1" line 18, in the Table, second column thereof, opposite "Benzol" read --l2'.-f-; and that thesaid Letters Patent should be read with this correction therein that the saine my; conform to the record of the case in the Patent Oiffi'ce.

Signed and sealed this 20thday of (Seal) November, I915.

Leslie Frezer"* First Assistant cmlsmnsr of Patents. 

